HOW TO FIND AND REPLACE YOUR AC FILTER

We are often asked what is the most important thing a homeowner can do to protect their air conditioning and heating system between maintenance and tune-up cycles?

It’s easy – change your air filter! Not only will it improve your indoor air quality and airflow, it also wards off expensive repairs and extends the lifespan of your expensive equipment.

Changing air filters is not that difficult for most homeowners, but there are usually two obstacles to getting it done:

  • Knowing when to change the filter
  • Knowing how to change the filter
  • Remembering to change the filter


When Do I Check/Change the AC Filter?

Simple, when they’re dirty, but how often depends on several factors:

  • The type of air filter you are using
  • Pets, number and type of pets
  • Occupancy levels of your home
  • Overall air quality, level of air pollution and construction around the home

Manufacturers generally advise changing your standard 1″-3″ filters every 60 days. However, if you suffer from light to moderate allergies, you may want to upgrade your air filter or change them more often.

We highly recommend setting a reminder to check your air filter every 30 days. While you may not to clean or replace it as frequently as that, it’s a good idea to check.

You can tell if you need to clean or replace the air filter by removing it from its chamber and holding it up to the light. If light can easily pass through the filter and it’s semi-transparent, leave it in. If it’s hard for light to pass through and it’s visibly dirty, change the filter. A dirty, clogged filter is no good!

Generally air filters should be replaced as follows:


Vacation home or single occupant no pets or allergies: 6-12 months
“Average” suburban home, no pets: 60-90 days
Add more than one pet or have allergies: 30-45 days

Why is the number of pets important? Pets tend to shed large amounts of hair, clogging filters quickly, which in turn can severely reduce the performance of your HVAC unit.

Where Is My Air Filter?

There are three main places where the air filter could be:

1. Where the return ducts enter the air handler, usually behind a 1-2” hinged cover. The filter should slide right out. Make sure the arrows on the filter are pointing in the direction of airflow.

2. Behind a louvered return air grill nearby. Keep in mind that there may be multiple filters in multiple returns. Access the filter by removing the grate (usually with a screwdriver).

3. Many homes have more than one filter. Check your blower compartment (indoor air handler) and behind the return grilles in your home.

Keep these things in mind when replacing your air filter:

  • Have a large garbage bag on hand to contain the dirty filter. Place the dirty filter in there as soon as you remove it. You don’t want all that trapped dust, dirt, and debris to reneter the home.
  • Make sure you have several replacement filters on hand. You don’t want to neglect this important home maintenance task just because you don’t want to make a trip to Home Depot.
  • Before purchasing replacement filters, speak with your local HVAC technician about which filer is best for you. You could probably purchase a filter with a higher MERV number to improve the air filtration in the home. Still, you want to make sure the filter is compatible first.
  • When replacing the air filter, vacuum and wipe around the filter area to keep the HVAC system as clean as possible.
  • While you’re at it, make sure there is a minimum 2-foot clearance around the indoor air handler.
  • Follow the instructions on the air filter carefully.
  • If you have a washable filter, clean it once a month and follow manufacturer instructions for cleaning. Consider speaking with your HVAC technician about switching over to disposable filters, which work better and are more convenient.
  • MAKE SURE THE ARROW POINTS IN THE DIRECTION OF THE AIRFLOW!

If you have any questions about air filtration, air purification, or HVAC topics in general, don’t hesitate to contact the experts at OnTime Service.

Schedule Service with OnTime Today!

Our HVAC tune-ups include a free air filter replacement and we would be more than happy to walk you through how and when to replace the filter.

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